Listen to the manufacturer! If you have MORE questions, call them first to get adapters or gas nozzles.

(By the way, they did NOT warn you "Do NOT EVER do this!" )

"N2 assist" will be flooding (cooling) the laser burner head with a non-flammable flood of non-toxic gas. By the way, monitor very, very carefully the oxygen levels of the room you are working within: Excess N2 will displace oxygen, and if too much oxygen is displaced with no outside ventilation, you will asphyxiate workers.

No they did not warn me at all. they instructed me to modify a cut condition I already have, but I don't have any for cardboard, I have one for plywood that works good. and several different metals.

If the cardboard and plywood are of similar total thicknesses, the cardboard should cut much easier than the plywood - BUT! - with more smoke and a greater chance of flames. This is because the cardboard is much, much thinner in each corrugation, and the air between each corrugation will let the hot "paper thin" cardboard get oxygen to burn once it reaches "char" temperature. The plywood is much denser, has no holes or vent paths, and so does not heat up locally as much.

BOTH the cut-off remnant falling towards the scrap heap AND the product left on the table will be hot enough to burn, smolder, and to potentially catch fire later in the pile in the corner, or the stack left in the rack. Consider a cooling flow of CO2 as well, plus a CO2 flood capacity in the room. And in the trash pile/trash bin.

Thanks for the advice just wanted to let you know that I have been successful in cutting 1/8" cardboard and 1/4"& 3/4" rubber floor mats thanks again